Addition agent for gasoline



Patented may 10,- 1949 2,469,737 nnm'rrou AGENT Foa GASOLINE .1 11930. Ml Nab, Cranford, and Barry W. Budd.

.. Nb-00mins;

This invention relates to motor-fuels?antler e lates more particularly to the stabilization-of tetraethyl lead in motor fuels.

mide, ethylene dichloride and other substances. in order to, increase the antiknock value of the motor fuel. Most of the gasoline now being sold contains some of this fluid, the amount varying from about 1-3 ccs. per gallon of gasoline. Fuel for special purposes such as aviation gasoline may contain even more. v

It has been found that upon storage, and especially upon exposure to sunlight, the tetraethyl lead tends to deteriorate or decompose with the production'of a haze or cloud formation in the gasoline and with subsequent deposition of a white precipitate. These lead deposits are most noticeable in sight glasses and in the glass bowls of gasoline pumps which become fouled and require frequent cleaning. Loss of the lead compound through precipitation also tends to lower the antiknock value of the motor fuel.

It has now been found that the addition of a' very small amount of the product obtained by the polymerization of alpha-beta unsaturated acid esters will stabilize the lead tetraethyl and retard deposition of deteriorated or partially decomposed tetraethyl lead, and furthermore will prevent the corrosion of metals in contact with wet fuel containing lead tetraethyl.

Polymerized alpha-beta unsaturated esters which may be employed in accordance with our invention to stabilize lead tetraethyl include polymerized esters of acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid and mesaconic acid and polymerized vinyl esters of fatty acids. These polymers should have a molecular weight of 2,000 to 30,000 or even higher and should be soluble in motor fuel.

The amount of stabilizer used depends on theamount of tetraethyl lead in the gasoline. It has been found that ordinarily 0.1 to 1% by weight of the above stabilizers based on the total weight of gasoline is sufficient for most purposes.

The stabilizers may be added to the gasoline directly or, if necessary, dissolved in a suitable solvent and then added to the gasoline in desired proportions.

The stabilizers may also be added to motor fuel adjuncts such as benzene or alcohol, antioxidants, solvent oils, deactivators etc., or with metal salts of acidic cyanic compounds etc.

These stabilizers may be added directly to the ethyl fluid with additional amounts of solvent, if necessary, and sold and shipped in this form. In this way the addition of tetraethyl lead to gasoline and addition of stabilizer occur simulta.

' conditions Jthe tetraethyl lead. In these tests a sample of arlz, J1, asslgnors to Standard 011 ompany,

a corporation of Dela- Application December 14, 1940, Serlalz1No.'716,432 v 116mm; (Cl 44-459) usavoiding any chance of decompositer the addition of ethyl fluid. -n--:or der to illustrate the effectiveness of these It is common practice to add to motor fuels a' jj. stabilizers, a number of them were tested under fluid composition consisting principally of tetraethyl lead and small'amounts of ethylene dibrotending to cause the decomposition of commercial aviation motor fuel containing 4 cc. of lead tetraethyl in a clear glass bottle was exposed to direct sunlight. Samples of the same gasoline but containing 0.01, 0.1 and 1.0% of various stabilizers of this invention were also exposed to the direct sunlight in the same manner.

' The results are given in the following table.

Concentra- Precipitation 0n Extion Wt. Per posure to Sunlight Polymer Cent Based on the Gasoline 1 Day 7 Days A commercial methyacrylic 0. 01 trace..- heavy.

polymer having a molecu- 0. 10 none o.

ler weight of about 15,000 1.0 ...do.. light.

repared by Rohm and aas.

An ester formed from l'u- 0. 01 traced" heavy.

maric acid and an alcohol with 1% benzoyl peroxide for 15 hours at 80 C. hav- 0. 10 none. medium.

lug a molecular weight of 1.0 -.do...- light.

about 2,000. Copolymer of decyl maleate- 0.01 none very light.

vinyl acetate. 0. 10 do none.

Y 1. 0 ..do. Do. hone heavy... very heavy.

1 Prepared by polymerizing a vinyl acetate with 1% benzoyl peroxide in 70% mineral oil solution for 16-24 hours at 80 C. and has a molecular weight of about commercial aviation fuel containing 4 cc. lead) stored in contact with polished steel test strips is indicated by the following data.

Cone Corrosion of Iron Test Strip Polymer Wt. Per

Cent 1 Day 7 Days A commercial methyacrylic 0. 10 Mediunn Heavy. polymer having a molec- 1.0 .....do -Do. ular weight of about 15,000 prepared by Rohm and Haas. An ester formed from i'u- 0. 10 Very Light" Medium. maric acid and an alcohol 1.0 -...-do Light. with 1% benzoyl peroxide for 15 hours at 80 C. having a molecular weight of about 2,000. Copolymer ofdecylmaleat Very Light.

and vinyl acetate. None. None Heavy Very Heavy;

The nature and objects of the present invention having been thus described and illustrated,

- what is claimed as new and useful and is desired to be secured by Letters Patent is:

1. A composition consisting essentially of tetraethyl lead and a small but stabilizing amount mixture of decyl maleate and ethyl lead and a small but stabilizing amountof a polymerized fumaric acid ester having a molecular weight of at least 2,000 to 30,000.

4. A composition consisting essentially of gasoline, suflicient tetraethyl lead to increase the antiknock properties'oi' the fuel and 0.01-1.0 weight per cent based on the gasoline of polymerized ester of an alpha-beta unsaturated acid having a mo; lecular weight of at least 2,000 to 30,000.

5. A composition consisting essentially of gasoline, sufilcient tetraethyl lead to increase the antiknock properties of the fuel and 0.01-1.0 weight per cent based on the gasoline of a copolymer of decyl maleate and vinyl acetate having a molecular weight of at least 2,000 to 30,000.

6. A composition consisting essentially of gasoline, sufiicient tetraethyi lead to increase the antiknock properties of the fuel and 0.01-1.0 weight per cent based on the gasoline of a polymerized '4' methacrylie acid ester having a molecular weight of at least 2,000 to 00,000.

7; A. composition consisting essentially of a motor fuel ofthe gasbline'typ'e containing up to 4 cc. of lead tetraethyl sufllcient to increase the antiknock properties of the fuel per gallon and from 0.01 to 1.0 weight percent of a polymerized ester of an alpha-beta unsaturated acid ester having a molecular weight of at least 2,000 to 30,000. v

8. A gasoline-containing motor fuel containing tetraethyl lead in-v amounts sufllcient to impart antiknock properties to said motor fuel and from 0.01 to 1.0 weight per cent of a polymerized ester of an alpha-beta unsaturated acid having a molecular weight of at least 2,000 to 30,000.

9. Gasoline containing about 4 cc. of tetraethyl lead per gallon and 0.01 to 1.0 weight per cent of a polymerized ester of an alpha-beta unsaturated acid having a molecular weight of at No references cited. 

